{"id":"UBUNTU-CVE-2023-46724","details":"Squid is a caching proxy for the Web. Due to an Improper Validation of Specified Index bug, Squid versions 3.3.0.1 through 5.9 and 6.0 prior to 6.4 compiled using `--with-openssl` are vulnerable to a Denial of Service attack against SSL Certificate validation. This problem allows a remote server to perform Denial of Service against Squid Proxy by initiating a TLS Handshake with a specially crafted SSL Certificate in a server certificate chain. This attack is limited to HTTPS and SSL-Bump. This bug is fixed in Squid version 6.4. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives. Those who you use a prepackaged version of Squid should refer to the package vendor for availability information on updated packages.","modified":"2026-02-04T02:24:04.973248Z","published":"2023-11-01T20:15:00Z","related":["USN-6500-1"],"upstream":["CVE-2023-46724"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2023-46724"},{"type":"REPORT","url":"https://github.com/squid-cache/squid/security/advisories/GHSA-73m6-jm96-c6r3"},{"type":"REPORT","url":"https://megamansec.github.io/Squid-Security-Audit/ssl-bufferunderread.html"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-6500-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2023-46724"}],"affected":[{"package":{"name":"squid3","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/squid3@3.5.12-1ubuntu7.16+esm6?arch=source&distro=esm-infra/xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.3.8-1ubuntu16","3.3.8-1ubuntu17","3.5.12-1ubuntu6","3.5.12-1ubuntu7","3.5.12-1ubuntu7.1","3.5.12-1ubuntu7.2","3.5.12-1ubuntu7.3","3.5.12-1ubuntu7.4","3.5.12-1ubuntu7.5","3.5.12-1ubuntu7.6","3.5.12-1ubuntu7.7","3.5.12-1ubuntu7.8","3.5.12-1ubuntu7.9","3.5.12-1ubuntu7.10","3.5.12-1ubuntu7.11","3.5.12-1ubuntu7.12","3.5.12-1ubuntu7.13","3.5.12-1ubuntu7.14","3.5.12-1ubuntu7.15","3.5.12-1ubuntu7.16","3.5.12-1ubuntu7.16+esm1","3.5.12-1ubuntu7.16+esm2","3.5.12-1ubuntu7.16+esm3","3.5.12-1ubuntu7.16+esm4","3.5.12-1ubuntu7.16+esm5","3.5.12-1ubuntu7.16+esm6"],"ecosystem_specific":{"binaries":[{"binary_version":"3.5.12-1ubuntu7.16+esm6","binary_name":"squid"},{"binary_version":"3.5.12-1ubuntu7.16+esm6","binary_name":"squid-cgi"},{"binary_version":"3.5.12-1ubuntu7.16+esm6","binary_name":"squid-common"},{"binary_version":"3.5.12-1ubuntu7.16+esm6","binary_name":"squid-purge"},{"binary_version":"3.5.12-1ubuntu7.16+esm6","binary_name":"squid3"},{"binary_version":"3.5.12-1ubuntu7.16+esm6","binary_name":"squidclient"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-46724.json"}},{"package":{"name":"squid3","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/squid3@3.5.27-1ubuntu1.14+esm5?arch=source&distro=esm-infra/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.5.23-5ubuntu1","3.5.23-5ubuntu2","3.5.27-1ubuntu1","3.5.27-1ubuntu1.1","3.5.27-1ubuntu1.2","3.5.27-1ubuntu1.3","3.5.27-1ubuntu1.4","3.5.27-1ubuntu1.5","3.5.27-1ubuntu1.6","3.5.27-1ubuntu1.7","3.5.27-1ubuntu1.8","3.5.27-1ubuntu1.9","3.5.27-1ubuntu1.10","3.5.27-1ubuntu1.11","3.5.27-1ubuntu1.12","3.5.27-1ubuntu1.13","3.5.27-1ubuntu1.14","3.5.27-1ubuntu1.14+esm1","3.5.27-1ubuntu1.14+esm2","3.5.27-1ubuntu1.14+esm3","3.5.27-1ubuntu1.14+esm4","3.5.27-1ubuntu1.14+esm5"],"ecosystem_specific":{"binaries":[{"binary_version":"3.5.27-1ubuntu1.14+esm5","binary_name":"squid"},{"binary_version":"3.5.27-1ubuntu1.14+esm5","binary_name":"squid-cgi"},{"binary_version":"3.5.27-1ubuntu1.14+esm5","binary_name":"squid-common"},{"binary_version":"3.5.27-1ubuntu1.14+esm5","binary_name":"squid-purge"},{"binary_version":"3.5.27-1ubuntu1.14+esm5","binary_name":"squid3"},{"binary_version":"3.5.27-1ubuntu1.14+esm5","binary_name":"squidclient"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-46724.json"}},{"package":{"name":"squid","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/squid@5.7-0ubuntu0.22.04.2?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.7-0ubuntu0.22.04.2"}]}],"versions":["4.13-10ubuntu5","5.2-1ubuntu1","5.2-1ubuntu3","5.2-1ubuntu4","5.2-1ubuntu4.1","5.2-1ubuntu4.2","5.2-1ubuntu4.3","5.7-0ubuntu0.22.04.1"],"ecosystem_specific":{"binaries":[{"binary_version":"5.7-0ubuntu0.22.04.2","binary_name":"squid"},{"binary_version":"5.7-0ubuntu0.22.04.2","binary_name":"squid-cgi"},{"binary_version":"5.7-0ubuntu0.22.04.2","binary_name":"squid-common"},{"binary_version":"5.7-0ubuntu0.22.04.2","binary_name":"squid-openssl"},{"binary_version":"5.7-0ubuntu0.22.04.2","binary_name":"squid-purge"},{"binary_version":"5.7-0ubuntu0.22.04.2","binary_name":"squidclient"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-46724.json"}},{"package":{"name":"squid","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/squid@6.1-2ubuntu2?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1-2ubuntu2"}]}],"versions":["6.1-2ubuntu1"],"ecosystem_specific":{"binaries":[{"binary_version":"6.1-2ubuntu2","binary_name":"squid"},{"binary_version":"6.1-2ubuntu2","binary_name":"squid-cgi"},{"binary_version":"6.1-2ubuntu2","binary_name":"squid-common"},{"binary_version":"6.1-2ubuntu2","binary_name":"squid-openssl"},{"binary_version":"6.1-2ubuntu2","binary_name":"squid-purge"},{"binary_version":"6.1-2ubuntu2","binary_name":"squidclient"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-46724.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}